Medium
S.36 on Glow-worm Ultracom 35 Store

Your boiler is working fine, but your external thermostat or programmer isn't telling it to turn the heating on.

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

No Heating demand from external controls 24V

From this model's manual
Verified against the Glow Worm Ultracom 2 Cxi installation & service manual, page 52.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This code appears when your boiler is ready to work but hasn't received a signal from your wall thermostat or timer to start heating the radiators. The most common reason is that the batteries in your wireless thermostat have run out or the timer is set to an 'off' period. It can also happen if the communication between your heating controls and the boiler has been interrupted.

This code is often seen during the first cold snap of autumn when homeowners first try to turn their heating back on after the summer break.

DIY fix possible

Check that your room thermostat is turned up higher than the current room temperature.Ensure your heating programmer or timer is set to 'ON' or 'AUTO'.Replace the batteries in your wireless room thermostat if the screen is blank or showing a low battery icon.

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